*Sigh*
 

Dang...

Bought a 256meg chunk of memory and the computer thinks it's 512meg. Lots
of errors in an ECC board (it's ECC memory) when running Memtest86, but in a
non ECC board Memtest wasn't finding any errors!!!??? Unfortunately I booted
to Windows and SPLAT! Didn't even make it to the desktop.

....oh well... RMA we go!